Here's Joe Johnson's rolling, game-by-game, year-to-date field goal shooting percentages.
This next graph may be of questionable value, so I'll explain (excuse?) how it came to be. Even though I'm glad to have sorted out and debugged my 2008-09 Hawks spreadsheet, it's still built on the old spreadsheet I created when writing primarily about college basketball several years ago. Working under the influence of John Gasaway, I measured the individual stats in terms of possessions. It's a necessary thing to do in college basketball because of the wild disparities in pace of play from team-to-team.
No one calculates NBA box score stats at a per possession rate. The disparity between the fastest and slowest NBA teams isn't significant enough that any added accuracy* gained by normalizing points, assists, or turnovers (to use the examples from the graph below) to 100 team possessions rather than 36 minutes** isn't worth the extra effort.
*And since I'm estimating possessions, there's probably not any added accuracy anyway.
**If you care, the league average pace (as of today) is 91.8. Pts/68.85 team possessions would be equivalent to Pts/36 Minutes.
But per 100 team possessions was the framework of the spreadsheet I've built upon and it's all I've got right now. I understand that it makes comparisons with other players in the league difficult. These graphs are a first step toward providing useful information (or, information usefully presented), not the last.
As always, please add any questions, suggestions, or additional compliments in the comments.